Rotor structure



Aug. 30, 1932. H. P. DAHLSTRAND 1,873,956

ROTOR STRUCTURE Filed May 5. 1950 Ame M64 Patented Aug. 30, 1932 HANS r. nAH srRANn; or wAUwA'rosA, Wisconsin, Ass'IGnoR TO'ALLrs-OnALME s MANUFACTURING- COMPANY, OF

. DELAWARE MILWAUKEE, Wisconsin, A OORPORATION or i. Y ROTOR srRncr RE Application filedmay 5,- 1930. Serial No. 449,786.

This invention relates to a means for main+ taining the centermg of a supporting or r ng member, suchas the blade carryingelement of a steam turbine, on a supporting shaft. 6 The high speeds at-which these turbines operate cause a corresponding amount of centrifugal force to be acting on the material of which the ring members are made. The diameter of the ring member increases with the IO'speed due to the increasedstress. Conse= quently, the ring members hadto be heated and shrunk onto the shaft in order that a rigid operative connection might stillbe had at the working speeds of the turbines; This 1 invention dispenses with the necessity of'heat treating the ring member and by merely providing a resilient element that is secured to the shaft at one end and that engages with the ring member at the other end to have a centered ring member at allworking speeds. On the drawing a pair of'ring members is shown mounted incontacting relation on ashaft of differentdiameters. v On the drawing 2 is the shaft; 3 and 4 the ring members; 5 and 6 the ring elements '5" 7 the keys for locking the ring members to the shaft-,8 and 9 are the shoulders on the shaft; 10-10 are the turbine blades; ll is the abut ment or annular flange on the ring element;

12 is the boreor internal diameterof the ring element; 13 the tubular portion of the ring element and 14 the bore of the ring'member.

In order to avoid the expense incidental to and danger in heating a ring member to shrink same onto a shaft that is to be rotated at high speeds, the applicant has invented the new and novel means for maintaining the centering of such a member, referred to above and now about to be more fully described. v

While two ring members are shown in con: tacting relation on the drawing itis notnecessary that they be so related nor-that a plurality be mounted on a shaft. The drawing described as used with ashaft of uniform diameter.

illustrates the invention used ing'connection As seen fromthe drawing, 4 may be any form or kind of a ring member'ofconsiderable'massand it may be keyed by a key 7 to a shaft 2 so as to be drivingly connected therewith. It will of course be understood that the invention is not limited to the shown key and slot means for effecting the driving connection betweenthe massive ring member and 'theshaft but any other suitable means may be used to accomplish this connection:.

Since the invention dispenses with the necessity of shrinking the ring member onto the shaft, the bore of the ring member may be'of the same diameter as that of the shaft orevenv of a slightly larger diameter. The boreof the ring member as shown is, however, not of a uniform diameter for reasons whichwill be presently stated r '6 is a ring element preferably of a material having a high elastic limit. Spring steel would be an ideal material from which to make such rings. The principal feature of the invention is to anchor 'or cause an interlocking relation between the outer periphery of the ring'element and the ring member while the innerperiphery of said element firmly grasps the shaft so as to, form arigid connection therewith. v

The. anchoring or interlocking relationbetween the said element and member may be obtained by providing the radiallydirected fiat portion of the ring element with a suitable fiange or abutment 11 that is received 7 in 'an annular groove, not numbered, in the ring member. v

It is apparent that the ring'element might be formed so as to have a fiat portion just r'eferredto and the flange or abutment 11, with the inner peripheral portion thereof in firm grasping contact with the shaft along a circumferential line that is not on the sur- 1 face ofthe shaft that is embraced or surrounded by thering member; o

However, in order tosave space applicant has designed the ring member so thatthe inner periphery of the ring element firmly grasps the surface ,ofthe shaft along a circumferential line that is on the surface of the shaft surrounded by the ring member. The ring element therefore isformed so as to have a tubular portion extendingfrom the flat or disk portion thereof in the same direction as the abutment or flange 11. The length of said tubular portion as shown may be considerably greater than the length of the key receiving slot provided in-thering member. In order that the describedpoin't of contact between the inner periphery of the ring element and shaft be had, the ring member 4: is provided with a bore of two different diameters the larger bore portion providing the space in which the tubular portion of the ring element is received. It

is preferable that the ring element .be provided with an annular flange that forms the surface of. contactbetween the ring element and the shaft. "Since the ring element -may be shrunk fit on the shaft, the diameter of the bore 12 of the annular flange, not *numr bered,:may be made less than the diameter of the shaft. 1

.:On the drawing 10 represents turbine or fan'blades that maybe carried by a massive ring member 4 rotating at high speeds in connection with which the invention is to be used. 7

Y The operation of the device is as follows. When .the massive ring member 4 is rotatingat high speed'there is'set up therein a corresponding centrifugal force. This subjects the material of which the ring member is made to a considerable stress which acts so as to enlarge the bore of the ring member and the member becomes uncentered. With thering element 6 as described engaging the ring m'ember, it remainscentered with respecttothe shaft over all operating speeds thereof even though they be high.

It should be understood that it is not desired to limit the invention to the exact de tails of construction herein shown and described, for various modifications withinthe scope of the claims may occur to persons skilled "in the art.

fIt-is claimed and desired to secure'by Letters Patent:

1. In COIIlblIlZLlDlOIl, a supporting shaft, a

. relatively flexible ring element having one portion rigidly associated with said shaft and having an abutment surface remote from said shaft and facing the same, and a relatively stiff and heavy ring member positively connected directly to said shaft inde pendently of'said ring element and engaging said surface.

2. In combination, a rotary support, 'a flexible ring element rigidly'attachedto said support and having an abutment surface spaced from said support and facing the axis thereof, and a relatively stiff and heavy ring member engaging said surface, said member being drivingly connected directly and independently of said ring element with said support.

F =In-combinati'on ,ia rotaryelementyarelatively massive member embracing and drivingly associated with said element, and a relatively resilient centering element snugly p t. i' d resiliimt "centering element. V

4. In combination, a rotarysup port, a massive "ring member mounted on said support so .ZLStO haveadriving connection therewith, and a relatively resilient centering ring havingnannu lar flanges at its outer and inner peripheral portions, the outer oneinterlocking with the ringmember and the :inner one being rigidly; attached 130 said support, the driving connectioniofrsaid massive member with said support being independent of saidrresilient centering ring. 1 5.-"In combination, a'rotary-shaft, a ring member mounted on said -sha-ftsoasto-have a driving connection therewith, 1y resilient centering ring havin annular flanges at'i-ts outerand innergperip heral portions, theoutelf'flangebeingreceived in anannu lar grooveisolated and spaced ilf-rom the shaftand providedin the ring member and therinnerflangesnugly fitting andbeing firm 1y secured-to-theshariathe driving connection of said member with said arotaryshaftbeing independent; of said centering ring. 7

"6-. In combination, a rotary shaft,-a massive ring membermeu-nted on-said shaft so=as to have a driving connection therewith, and an L-shaped relatively jflexible ring element having two annular flanges, one i of said flanges :being directed toward [and firmly pressing against said shaft and the other flange being received in fan annular :groove isolated an'dispace'd from the shaft and provided in said ring member, the driving connectionofsaid massive-member with saidrotargy shaft-being independent of said flexible ringwelement. c I

7 In"conrbination, a rotary shaft, a massive ring membenmounted on said shaft so as 1-tohave .-adriving connection therewith,

said-memberz'havingra bore-70f different diamete'r-s, oneportion of's'aid bore closely approximating -the I diameter ;of the shaft while the other portion is of alarger diameter,a relatively flexible ring element snugly fitting said shaft, and ha'ving onepartzthereofpositioned in the space betweenthe-shaft and-the wall of the bore of-greatest diameter and connected with the ring member throug'hanother part of said'elemeut,torestrai-n outward displace ments 'of said :rinjg-memberii-n a plurality'of radialdirections. 8. In combination, a -rotaryyshafua ring member mountedaon s'ai-d: shaft, saidmember having a bore of different diameters,-on e;por}

and a relative-- tion of said bore closely approximating the diameter of the shaft and cooperating to pro vide a driving connection between said massive member and said rotary shaft, the other portion of said bore being of a larger diameter, a relatively resilient ring element rigidly connected to said shaft, and having one part thereof positioned in the space between the shaft and the wall of the bore portion of greatest diameter, and firmly secured to'the ring member through another part thereof, to restrain outward displacements of said ring member in a plurality of radial directions.

9. In combination, a rotary shaft, a ring member mounted on said shaft so as to have a drivlng connection therewith, means for forming said driving connection, and arelatively resilient centering ring having a tubular portion and a disk portion, the tubular portion firmly grasping said shaft and the disk portion being provided with means cooperating with said ring member, for effect ing an outwardly coupled connection between said centering ring and said ring member.

10. In combination, a rotary shaft, a ring member having a shaft receiving bore of different diameters, a relatively resilient centering ring having a part closely surrounding the shaft and received within a space bounded by said shaft and the wall of the bore portion of greater diameter, said centering ring further having a part located eXteriorly of said space and engaging said ring member, and means forming a driving connection between said ring member and said shaft.

11. In combination, a rotary shaft, a ring member having a shaft receiving bore of. different diameters, a resilient centering ring having a part closely surrounding and rigid-, ly secured to said shaft and received within a space bounded by said shaft and the wall of the bore portion of larger diameter, said centering ring further having a part located exteriorly of said space and inwardly engaging said ring member, and means forming a driving connection between said ring member and said shaft, said means being located contiguous to the lesser diameter bore portion of said ring member.

In testimony whereof, the signature of the inventor is affixed hereto.

HANS P. DAHLSTRAND. 

